With fast developments of display technologies, touch screen panels have been gradually popularized in people's life. Currently, according to working principles, touch panels can be divided into a resistance type, a capacitive type, an infrared ray type and a surface acoustic wave type. The capacitive type in-cell touch panel is very popular with the industry due to its distinct touch principle and advantages such as high sensitivity, long service life, high light transmittance and etc.
Traditional capacitive type in-cell touch panels are achieved through directly providing additional touch scanning lines and touch sensing lines on a TFT (Thin Film Transistor) array substrate, that is, two layers of strip ITO electrodes crossing each other at different planes are fabricated at the surface of the TFT array substrate, and the two layers of ITO (Indium Tin Oxides) electrodes respectively serve as the touch scanning lines and the touch sensing lines of the touch panel, and a sensing capacitance is formed at the intersection of different planes of two strip ITO electrodes. When a human body touches the touch panel, the capacitance value of the sensing capacitance changes, then the voltage signal coupled by the touch sensing lines is changed, and the position of the touch point can be determined according to changes of the voltage signal.
The manner of fabricating two layers of strip ITO electrodes crossing each other at different planes at the surface of the TFT array substrate will increase the thickness of the TFT array substrate, needs additional power to drive the touch structure and decreases the transmittance of the array substrate.
Currently, it becomes a mainstream research direction in the industry that the elements in a current display panel are multiplexed and made to achieve a touch function.
FIG. 1 is a structural schematic diagram of the array substrate provided by the prior art, and FIG. 2 is a partial enlarged view of structure A shown in FIG. 1. As shown in FIGS. 1 and 2, the array substrate comprises a base substrate plate 1 on which several common electrode bases 4 are formed. The common electrode bases 4 are grouped in a manner of connecting the common electrode bases 4 through a common electrode line (Vcom line), and the common electrode bases 4 are divided into a transverse electrode group and a longitudinal electrode group. The common electrode line comprises a transverse electrode line 301 (H-Vcom line) and a longitudinal electrode line 201 (V-Vcom line). A longitudinal electrode group is formed between two transverse electrode groups adjacent to each other in the transverse direction, two transverse electrode groups adjacent to each other in the longitudinal direction are circuit broken therebetween, and at least one transverse electrode group is formed between two adjacent longitudinal electrode groups. The transverse electrode groups adjacent to each other in the transverse direction can be connected with each other through a metal jumper wire 302 to form a horizontal common electrode 3, the longitudinal electrode groups in the longitudinal direction separately constitute a vertical common electrode 2, and the metal jumper wire 302 bypasses the vertical common electrode 2.
At a display scan phase, the horizontal common electrode 3 and the vertical common electrode 2 cooperate with pixel units to achieve a display function.
At a touch scanning phase, one of the horizontal common electrode 3 and the vertical common electrode 2 is used as a touch scanning line and the other one is used as a touch sensing line. The metal jumper wire 302 in the horizontal common electrode 3 forms a sensing capacitance with the common electrode bases 4 or the horizontal electrode line 201 in the vertical common electrode 2 at the place where they cross. When a human body touches, the capacitance value of the sensing capacitance changes, then the voltage signals coupled by the touch sensing line are changed, and the position of the touch point can be determined according to the changes of the voltage signals.
In addition, in the prior art, the two transverse electrode groups adjacent to each other in the transverse direction can also be connected with each other via a transverse electrode line 301 which bypasses the vertical common electrode 2. At the touch scanning phase, the transverse electrode line 301 forms a sensing capacitance with the common electrode bases 4 or the horizontal electrode line 201 in the vertical common electrode 2 at the place where they cross. When a human body touches, the capacitance value of the sensing capacitance changes, then the voltage signals coupled by the touch sensing line are changed, and the position of the touch point can be determined according to the changes of the voltage signals.
The existing technical solutions, however, have disadvantages. At the touch scanning phase, as the common electrode bases and the common electrode line are constituted by an ITO material, this results in a large resistance of the horizontal common electrode and the vertical common electrode and then a large resistance of the touch scanning line and the touch sensing line, and then does not help detect the voltage signals coupled by the touch sensing line, and then results in inaccurate positioning of the touch point.